textproduct: Rapid City

KEY MESSAGES

- Above average temperatures remain in the forecast. The hottest day will be today with highs in the mid to upper 90s with 80s and 90s expected Sunday and Monday.

- Elevated fire weather conditions are expected through the weekend.

- Isolated to scattered thunderstorms are expected through Sunday, focusing on this evening and Sunday afternoon/evening

UPDATE

Issued at 1032 PM MDT Sat Sep 5 2026

Storms have moved out of the region, though elevated instability remains across much of the region with recent mesoanalysis depicting 1000-2000 J/kg MUCAPE over much of the western SD plains. With a lack of forcing, we likely won't see much, if any, convection overnight. Still looking like we'll see chances for storms tomorrow afternoon and evening as a shortwave grazes the region. Have made no major changes to the forecast aside from some minor adjustments to PoPs overnight into tomorrow afternoon based off of latest CAMs.

DISCUSSION

(This Afternoon Through Friday) Issued at 1139 AM MDT Sat Sep 5 2026

For the rest of today, isolated storms are drifting northwards. But with weak flow and weak large scale forcing, storm coverage will be limited, which will help lower the overall severe risk. Enough instability exists that severe wind gusts and severe hail are possible. For now, thinking is these storms drifting northwards will travel east to northeast this afternoon, tracking through the SD plains through tonight. Today's afternoon temps will be much above normal, in the 90s to near 100. Overnight temps will cool to the 60s for most of the area, little cooler in the Black Hills.

Around round of passing storms is likely tomorrow/Sunday. An upper level trough, currently sitting and spinning over the pacific northwest, will swing over Montana. This trough will likely be the main weather maker for the area for a couple days. As it kicks east and north, thunderstorms will be likely ahead of the trough. And this kind of pattern has had a history of producing severe weather. The SPC has placed a marginal severe risk out for Sunday over the Black Hills and to the north and machine learning severe weather models are hinting at the risk of severe weather centered over the CWA Sunday into Monday. For now, thunderstorms will likely get going around noon over the Black Hills and those will track northward. Then late Sunday into Sunday night, a reinforcing round of moisture and storms will drift northward through the area. Now is a good time to be sure of having a way of being informed of severe weather in your area.

For next week, very low chances for precip lingers in the forecast with slightly cooler weather Tuesday and Wednesday, before the upper 80s to 90s return later in the week.

AVIATION

(For the 12Z TAFS Through 12Z Monday Morning) Issued At 529 AM MDT Sun Sep 6 2026

Isolated to scattered thunderstorms will develop this afternoon/evening with local MVFR conditions. Have left storms out of the terminals for now given low confidence in location of convective initiation Sunday afternoon. Outside of thunderstorms, VFR conditions are expected through the period.

FIRE WEATHER

Issued At 1139 AM MDT Sat Sep 5 2026

Warm and dry conditions are still found around the area today, especially over northeastern WY and parts of western SD but the winds aren't as strong as they have been. So elevated fire weather conditions are expected today.

Temperatures will be hot again tomorrow and Sunday with highs well into the 90s to near 100 degrees. Very low humidity is also expected to continue, dropping to near 15 to 20 percent in the afternoons across northeastern WY and portions of far western SD. The winds will continue to be not as strong, so at this time, Red Flag Warning thresholds are not expected to be met so a Red Flag Warning extension is not expected at this time.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.